finding the location of header (.h) files

[mick]

I have an application that depends on gtkhtml-2.0, which seems to be in a 
diferent location in almost every linux or BSD distribution.

Currently I have:- 
INCLUDES = -I/usr/include/gtkhtml-2.0
in Makefile.am and 
AC_CHECK_LIB([gtkhtml-2], [html_document_open_stream],, [AC_MSG_ERROR([BUMMER, 
Maybe if you install libgtkhtml-2 & libgtkhtml-2-dev this pig will fly])])
in configure.ac, which works on my system but I need to replace it with a 
portable construct to tell autoconf/make etc. to find it and feed its 
location into the final Makefile.

I have searched through autoconf and automake.pdf's but if I saw what I need I 
didn't recognise it.

please help
/]/]ik